A Pulmonary Embolism hospitalized Serena Williams’s last month. Serena Williams was hospitalized in Los Angeles and she required emergency treatment Monday for a hematoma, a pocket of blood that swells under the skin.

A pulmonary embolism — a clot that blocks blood flow to the lungs — can be life threatening in severe cases, but Williams’s spokeswoman, Nicole Chabat, said in a statement Wednesday that “thankfully everything was caught in time” and that Williams was resting and recovering at her home in Los Angeles.

Williams was previously injured and had been in a cast and a walking boot, which was removed last month. But Williams’s longtime agent, Jill Smoller, said in a telephone interview Wednesday that the pulmonary embolism — first reported by People Magazine’s Web site — was detected after Williams returned to Los Angeles from New York last month. Smoller said it required Williams to be “hospitalized for the weekend” of Feb. 19 and 20 at Cedars-Sinai Medical Center.

Dr. Byron Thomashow, a pulmonary specialist said that pulmonary emboli “are not uncommon,” and that “almost always, they come from a clot in the leg that travels up to the lungs, and there is treatment that can certainly be very successful,” Thomashow said. “Most pulmonary emboli are not life threatening.”

“What I tell people generally is, once you’re on the medication, you are generally safe,” he said. “You can go out and do whatever you want to do within reason. You don’t want to get into fistfights or anything that’s going to make you bleed.”

Williams was treated with anti-coagulant drugs, commonly known as blood thinners, after her operation in October. Morrissey said that the use of such drugs could increase the risk of a patient’s forming a hematoma.

Pulmonary embolisms occur when blood is allowed to pool for too long, forming a clot. The clot travels through the circulatory system and lodges in the lungs, blocking the flow of oxygen. It can cause lasting damage … or kill its victim instantly.

Doctors know – or at least they should – which patients are most at risk for pulmonary embolisms. If they fail to take proper preventive measures and their patient dies as a result, their oversight may be considered malpractice.

Experts say Pulmonary Embolism’s are more common in those who’ve been confined to bed rest for some time, but can also occur when people travel long distances and sit in a cramped position, like reporter David Bloom who died in 2003. This kind of inactivity often leads to blood clots in the legs, or deep-vein thrombosis. Surgery, particularly knee and hip replacement surgery, can also lead to blood clots.

At least 100,000 cases of pulmonary embolism occur in the United States each year. And it’s the third most-common cause of death in hospitalized patients, according to the National Heart Lung and Blood Institute. If left untreated, about one third of patients will die.

How do you know if you’re experiencing a pulmonary embolism?

The most common symptoms include shortness of breath — even when you’re not exerting yourself — along with chest pain and coughing up blood. If you experience any of these symptoms, see a doctor immediately.

In some cases, the only signs and symptoms are related to deep vein thrombosis, according to the National Heart Lung and Blood Institute. Signs include swelling of the leg or along the vein in the leg, pain or tenderness in the leg, a feeling of increased warmth in the area of the leg that’s swollen or tender, and red or discolored skin on the affected leg.

Other symptoms to watch for include:

•Excessive sweating

•Clammy or bluish skin

•Light-headedness

•Fast or irregular heartbeat

•Weak pulse

The risk of developing a pulmonary embolism increases as you age. For every 10 years after age 60, the risk of a pulmonary embolism doubles.

As a Miami Medical Malpractice Lawyer I brought a wrongful death lawsuit on behalf of the family of a man who died needlessly because of a pulmonary embolism after he underwent a radical ankle procedure that resulted in a prolonged period of immobility. He began to gain weight and was non-weight bearing. These two factors can lead to the “blood-pooling” effect that causes pulmonary embolisms. The doctor should have recognized this and put our client on a healthy dose of anti-coagulant medication – but he didn’t.

Compounding the situation was the doctor’s failure to diagnose the pulmonary embolism once it began to take effect. While there are guidelines for Anti-Coagulation following Knee and Hip replacement surgery, there are no applicable guidelines published by either the American College of Chest Surgeons or the Academy of Orthopaedic Surgeons for Ankle Surgery. Thus, doctors must weigh all the potential risk factors of their individual patients and weigh those risk factors against the potential side effects of Anti Coagulant therapy-which includes bleeding and death.

Mark Kaire has been practicing law in Miami for nearly 15 years. He is dedicated to helping the injured people of Miami receive compensation. Mr. Kaire has been blogging on Miami’s legal issues for 4 years.